For me my inventory on hand is more about the lead times on the commonly used items from my vendors. At one time I stocked a larger amount of parts as to get volume discounts. Now with several distributors in the mix it is a lot easier for me to only keep one or two of an item. Of course I still buy fuel line in bulk of either 25' or 50' rolls. Here I stock the 1/4 and 3/16 nitrile rubber fuel lines; hardly ever need a 5/16 line. Now on the Tygon I usually only use two sizes and a couple Echo line sizes. Just something I got use to as most customers are looking for a quick turn around if just a fuel line problem. One thing to help out on the bottom line is buy your hardware in bulk of the item you commonly use. Say a box of 25 hex screws especially the metric ones. Here a single hex screw is nearly as much as half of a box.
Have items in stock is nice but having items that you rarely use can really hurt your available cash to purchases plus keeping track in a pain unless you have software and use a binning system to help keep track of the inventory. BTW I am getting ready for annual inventory check as few items got superseded and the software didn't carry Bin location forward. What a pain when you got 20K in parts to have item that you know that you darn well have but can't find it because of a lost bin location. Keeping a track of 1600 different items can overwhelm you without a good tracking system.
With the distributors I now have it is one or two days deliveries so I am not as pressed to keep parts on hand. Way better those that are 1 to 2 weeks out on deliveries. Even with this improvement I still have over 26K in inventory; although, it is down from 35K. Still a heck of a lot to have on hand to do 20K in annual business but turn around times is important to me as I need to keep things cleared out as much as I can. Just don't like long term projects like the one I just finished that took over 2 months to complete but of course I was out of commission for nearly a month and still losing afternoons due to dizziness.
Here is a copy my inventory totals here. Now course the sales looks like I didn't much more in value than last year but my costs are down considerable plus I was able sell at a greater profit while still lowering my customer's costs.
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